package collection;

import java.util.ArrayList;
import java.util.Collection;

public class CollectionDemo1 {
	public static void main(String[] args) {
		Collection c = new ArrayList();
		c.add("one");
		c.add("two");
		c.add("three");
		c.add("four");
		
		System.out.println("集合大小："+c.size());
		System.out.println("是否为空集:"+c.isEmpty());
		
		c.clear();
		System.out.println("集合已清理");
		System.out.println(c);
		System.out.println("集合大小："+c.size());
		System.out.println("是否为空集："+c.isEmpty());
	}
}
